Protecting personal computers against a never-ending onslaught of “pestware” such as viruses, Trojan horses, spyware, adware, and downloaders on personal computers has become vitally important to computer users. Some pestware is merely annoying to the user or degrades system performance. Other pestware is highly malicious.
Many computer users depend on anti-pestware software that attempts to detect and remove pestware automatically. Anti-pestware software typically scans running processes in memory and files contained on storage devices such as disk drives, comparing them, at expected locations, against a set of “signatures” that identify specific, known types of pestware. Difficulties arise, however, when pestware hides itself from the operating system of the computer. One way in which pestware hides itself is by hooking one or more Application-Program-Interface (API) functions of the operating system, changing the way they operate in a manner that renders the pestware undetectable by the operating system. The resulting hidden pestware file is sometimes referred to as a “rootkit-masked file.” Conventional anti-pestware software does not always detect such hidden pestware files.
It is thus apparent that there is a need in the art for an improved method and system for detecting and removing hidden pestware files.